Aqueous and methanol extracts of Parrotia persica leaves were assayed for antifungal activity against phytopathogenic Fusarium oxysporum and human pathogenic Candida albicans by poisoned food technique. Both the aqueous and methanol extracts demonstrated significant antifungal activity. Further fractionation of methanol extract guided by antifungal activity resulted in the isolation of an active principle which was identified as phenolic compound by phytochemical analysis. The structure of the active principle was elucidated by Mass spectroscopy, 1H NMR and 13C NMR spectroscopy. These results revealed that the compound is 6-(ethoxymethyl)-tetrahydro-2H-pyran-2, 3, 4, 5-tetraol compound with 1-isopropyl-4-methoxybenzene. The compound was found responsible for antifungal activity against both F. oxysporum and Candida albicans.